The Naval Surface Warfare Center on Wednesday unveiled its newly rebuilt 12.2-million-gallon “wavemaker” in Carderock, Maryland. The massive pool of water—400 by 300 feet across and 20 to 35 feet deep—makes waves as high as four feet, which are used to test scale models of warships and submarines.
“It never gets old for me,” said Jon F. Extegoien, sounding like a new father, as a small group of visitors stood at the edge of the water and, as if at the beach, gazed dreamily at the waves. Extegoien, head of naval architecture and engineering at the warfare center, showed off a variety of human-created waves, pointing out that the giant paddles that move the water can recreate the same wave over and over with 99 percent accuracy. They are in effect almost perfect man-made waves. “We’re still in calibration mode for the next seven weeks,” he says. A 20-foot model of the new 750-foot Zumwalt-class destroyer will be the first ship tested. “Bath Iron Works just floated it,” he said. “It’s not finished yet. Now they will be putting systems on board.”
Because the new wavemaker can quickly “calm” the water before starting a new series of waves, it allows for more, and more efficient, tests. The tank is filled with fresh, not salt, water. To allow for the scientific impact of salt water “we have to make a correction in resistance testing, which is a straight-line test, because we really can’t afford to introduce salt water,” he said. “It’s so destructive. The maintenance is just ridiculous.” If needed, on the grounds is a 140-foot tank that can be filled with salt water.
There’s one particular type of wave that is missing from the wavemaker’s menu, and on purpose. Rogue waves are among the most fearsome in the open sea, because they are large and unpredictable. As they are caused by many different factors, they don't fit into the statistical models used by Extegoien. When we asked about rogues, he made a face. “You hit on a bad spot for us. We don't like that term,” he said. The wavemaker, however, reproduces something similar to a “rogue” when it creates large waves that come from two different directions.
Check out a video of the wavemaker in action below.